Support is requested for organizing the Sixth Conference on Hemoglobin Switching to take place in September 1988. It will represent a gathering of molecular biologists, cell biologists, developmental biologists, and clinical investigators who are directly involved with studies on molecular biology of globin genes and hemopoietic cell differentiation. The duration of the conference will be three days. International participation is anticipated, and support for travel and/or lodging expenses for 15 foreign and 45 USA participants is requested.